用于描述变异程度的指标是（）
A.总体均数
B.样本均数
C.中位数
D.标准差
E.相对数
参考答案：D
We’ d better try to the plan again, I think, before we with it.
A．go through/ go on
B．go on/ go over
C．go over/ go through
D．go on/ go through
学校体育的基本特性是_____、_____和_____。
